1. Field of the Invention
This invention is related to electrical connectors of the type that can be mated and unmated. This invention is also related to the prevention of arcing between mating terminals as electrical connectors are mated or unmated in a hot condition. This invention is also related to the use of a shunt to provide a signal to close a relay to bypass current around the electrical connectors during mating and unmating to reduce the chance of arcing.
2. Description of the Prior Art
Arcing can be a problem when electrical connectors are mated and unmated under load or in a hot condition. If arcing between mating electrical terminals does occur, it would normally occur when the terminals are initially mated or unmated and the terminals are either not in contact or have not been brought into sufficient contact to carry the current
The replacement of a 14 volt system with a 42 volt electrical architecture for automobiles increases the chance that an arc can form if electrical connectors are mated and unmated under load. However, it would be rather expensive to adopt systems for arc avoidance, prevention or suppression that are commonly used for systems with a higher voltage or more current carrying capacity. Applicants are not aware of a simple, existing, inexpensive system using terminals of substantially the same type as are used in current automotive electrical systems and introducing a minimum amount of additional leads or wires. The addition of sacrificial pins that make first and break last to avoid arcing for shorter contact in the same current path requires new terminals and new connectors and increases the contact density.
Shunts have been used to common adjacent contacts in the same connector when unmated from a mating connector. For example, shunts of this type are commonly used in air bag connector. However, applicants are unaware of the use of a single shunt in one of two mating connectors to provide a signal to a relay to bypass current around the electrical connector before mating terminals are in a position where they would be susceptible to arcing.
The instant invention employs a single shunt to provide a signal for bypassing an electrical connector assembly before the mating terminals have reached a position in which arcing can occur between two terminals. Only a single shunt and a single lead needs to be added to an electrical connector. This reduces the number of leads that would be needed for a make first, break last sacrificial contact. Furthermore the single lead can be connected to a switch, such as a Form C relay, that can be used in the electrical system of an automobile. The relay can be connected to a circuit path that bypasses the electrical connector assembly when a signal is received through the shunt to close the Form C relay.
In a preferred embodiment, the relay is a solid state relay device such as that disclosed in U.S. Pat. No. 5,926,354 or, most preferably, that disclosed in U.S. patent application Ser. No. 10/068,925, filed Feb. 8, 2002. These references disclose solid state relays including a power metal oxide semiconductor field effect transducer (xe2x80x9cMOSFExe2x80x9d). In the latter reference, the circuitry of the relay floats when the power MOSFET is commanded OFF to prevent leakage currents from draining a battery. The disclosures of these references are incorporated herein by reference in their entirety.
FIG. 1 is diagrammatic view of an electrical connector assembly showing two fully mated electrical connectors with a shunt in one connector held in a deflected position by engagement with a surface on the other electrical connector.
FIG. 2 is a diagrammatic view of a partially mated electrical connector assembly in which the shunt is in contact with a terminal in the other electrical connector. Mating terminals are still in contact and the terminals are approaching a position in which arcing might occur.
FIG. 3 is a diagrammatic view of the two electrical connectors in an unmated configuration in which the shunt is in an undeflected configuration.
FIG. 4 is a diagrammatic view of a circuit in which a Form C relay has been closed to bypass current around an electrical connector assembly before arcing can occur.
FIG. 5 is a sectional view of a representative embodiment of mating electrical connectors incorporating the instant invention.